I have 3 Activities - A, B, and C.
In a nutshell, Activity A starts Activity B, then A also starts Activity C and
I was never able to get this to work, so I ended up using a Handler instead to return the data to the necessary Activity.
UPDATE: After running into this again, I found out that the real reason this wasn't working is because I had android:noHistory="true"
for the calling/receiving Activity A in the manifest. Removing android:noHistory="true"
fixed it, but if you need it to be true, then Handlers are a good workaround.